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51.
The effects of streptozotocin-induced (STZ) diabetes on the response to immobilization stress were evaluated in adult male rats. Rats were injected with STZ or vehicle and handled daily to minimize stress. Four weeks later, half of the animals were lightly anesthetized with ether and immobilized for 20 min. At that time the stressed and nonstressed controls were sacrificed, and blood and tissue collected for hormone and amine determinations. Immobilization caused an increase in plasma glucose levels in the controls, but caused no further increase in the already high levels seen in the diabetic rats. Basal corticosterone levels did not differ between the STZ and control rats, and the increase after immobilization was of similar magnitude. The stress-induced increase in prolactin was attenuated in the diabetic rats. Immobilization caused a significant rise in plasma norepinephrine (NE) levels in control, but not in diabetic rats. Adrenal NE content and tyrosine hydroxylase activity were not significantly affected by stress or STZ treatment. Dopamine (DA) and NE content was increased in the hypothalamus of immobilized diabetic rats as compared to nondiabetic immobilized controls. These results demonstrate that diabetic rats respond to immobilization stress, but the endocrine and sympathetic nervous system response is impaired. Changes in the stress response may be related to changes in hypothalamic amine metabolism.  相似文献   
52.
Patients with solid tumors are increasingly being treated by autologous bone marrow transplantation (BMT). Although response rates appear to be increased, disease recurrence is the commonest cause of treatment failure. Whether relapse is entirely due to residual disease in the patient or arises also from infiltrating malignant cells contained in the autologous marrow transplant has not been resolved. If the latter explanation is correct, then purging would be required as part of the transplantation procedure. We used retrovirally mediated transfer of the neomycin-resistance gene to mark BM harvested from eight patients with neuroblastoma in clinical remission. The marked marrow cells were subsequently reinfused as part of an autologous BMT. At relapse, we sought the marker gene in malignant cell populations. Three patients have relapsed, and in each the marker gene was detected by phenotypic and genetic analyses of resurgent malignant cells at medullary and extramedullary sites. Analysis of neuroblast DNA for discrete marker gene integration sites suggested that at least 200 malignant cells, each capable of tumor formation, were introduced with the autologous marrow transplant and contributed to relapse. Thus, autologous BMTs administered to patients with this solid tumor may contain a multiplicity of malignant cells that subsequently contribute to relapse. The marker-gene technique we describe should permit evaluation of the mechanisms of relapse and the efficacy of purging in patients receiving autologous marrow transplantation for other solid tumors that infiltrate the marrow.  相似文献   
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Iliopsoas impingement is a commonly recognised source of groin pain following total hip replacement. When conservative measures fail, open or arthroscopic iliopsoas tendon release can reliably alleviate pain and improve function. This article describes an alternative ultrasound‐guided percutaneous technique, achieving iliopsoas tenotomy utilising a modified 18G coaxial needle and thus minimising the morbidity and cost associated with an open or arthroscopic procedure. This method proved successful with resultant complete resolution of patient symptoms. To the knowledge of the authors, this is the first case of ultrasound‐guided percutaneous iliopsoas tenotomy for iliopsoas impingement post total hip replacement.  相似文献   
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Background

We previously demonstrated that A-type natriuretic peptide (ANP) at peak exercise was an independent predictor of cardiac survival. No data are available concerning the predictive value of B-type natriuretic peptide (BNP) at peak exercise.

Methods

One hundred and fifty consecutive stable patients with moderate congestive heart failure (CHF) underwent echocardiography and a cardiopulmonary exercise test. Blood samples were drawn at rest and at peak exercise for the determination of plasma levels of ANP, BNP, and norepinephrine.

Results

Exercise significantly increased plasma values of ANP, BNP, and norepinephrine. After a median follow-up period of 1171 days, there were 35 cardiac related deaths. Mortality rates at 1 and 2 years were 4% and 8%, respectively. Independent predictors of cardiac survival were percent of maximal predicted oxygen consumption (RR = 4.8 [2.1-11], P = .002), BNP at rest (RR = 2.5 [1.2-5.6], P = .01), and left atrial diameter (RR = 2.8 [1.2-6.5], P = .02).

Conclusions

In patients with stable, moderate CHF, plasma levels of ANP, BNP, and norepinephrine measured at peak exercise did not improve risk stratification. However, in addition to percent of maximal predicted oxygen consumption and left atrial diameter, plasma level of BNP at rest was an independent predictor of survival in CHF patients with low risk of cardiac events.  相似文献   
57.
OBJECTIVE: Discordant results have been published regarding a possible association between beta-adrenoreceptor (betaAR) gene polymorphisms and survival in patients with congestive heart failure (CHF). The aim of the study was to analyze the impact of five functional betaAR gene polymorphisms in patients with stable CHF. METHODS: We prospectively studied 444 consecutive patients with CHF related to left ventricular systolic dysfunction. The beta1ARSer49Gly, beta1ARGly389Arg, beta2AR Arg16Gly, beta2AR Gln27Glu and beta2AR Thr164Ile polymorphisms were determined. Patients underwent echocardiography, radionuclide angiography and a cardiopulmonary exercise test. RESULTS: Mean age was 56.6+/-11.9 years old, left ventricular ejection fraction (LVEF) was 32+/-12%, and peak VO2 was 15.5+/-4.9 ml/min/kg or 63+/-18% of maximal predicted VO2. Most of the patients (95%) were receiving angiotensin converting enzyme inhibitors and 91% beta-blockers. There was no statistically significant differences between baseline characteristics among beta1AR and beta2AR genotypes. During a median follow-up period of 1232 days, there were 110 cardiac-related deaths and five urgent transplantations. Independent predictors of survival were percent (%) of maximal predicted VO2 (p<0.0001), age (p<0.0001), LVEF (p=0.004), creatinine (p=0.02) and atrial fibrillation (p=0.04). No betaAR polymorphisms were associated with survival. However, patients with the combined beta2ARGly16Gly/beta2ARGln27Gln genotype, who express receptors highly sensitive to down-regulation, had a significantly lower survival rate than patients with other genotypes but only in univariate analysis. CONCLUSIONS: In this prospective study, we found no association between five functional betaAR polymorphisms and survival in patients with stable CHF. However, we demonstrated, only in univariate analysis, a possible association between the combined beta2ARGly16Gly/beta2ARGln27Gln genotype and survival.  相似文献   
58.
5-羟色胺对气道平滑肌细胞增生的影响及c-fos的表达   总被引:7,自引:0,他引:7  
5-羟色胺对气道平滑肌细胞增生的影响及c-fos的表达刘振千梁凤珍马军红戚好文为了探讨哮喘气道平滑肌层增厚的机制,考察哮喘的炎性介质5-羟色胺(5-HT)对兔气道平滑肌细胞(ASMC)增生的影响及原癌基因c-fos的表达。新西兰大白兔,抗α-肌动蛋白...  相似文献   
59.
Samoszuk  MK; Espinoza  FP 《Blood》1987,70(2):597-599
Eosinophil granules are intensely autofluorescent when excited by green light. To determine if eosinophils degranulate in the bone marrows of patients with a variety of diseases, we used green light epifluorescence microscopy to examine deparaffinized and dezenkerized sections of 49 bone marrow core biopsies. In 14 of the biopsies, there was striking extracellular deposition of intensely autofluorescent eosinophil granules in addition to numerous intact eosinophils. Among the 14 specimens with extracellular autofluorescence were seven cases of leukemia, four cases of non-Hodgkin's lymphoma, two cases of myelofibrosis, and one case of pancytopenia with eosinophilia. In the remaining 35 specimens, only intact eosinophils were identifiable. There was no extracellular autofluorescence in three normal marrows, four marrows from AIDS patients, or three biopsies from patients with idiopathic thrombocytopenic purpura (ITP). We conclude that green light epifluorescence microscopy identifies extracellular deposits of eosinophil granules in bone marrow biopsies of some neoplastic disorders and in diseases associated with reticulin fibrosis.  相似文献   
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